Category Physics

In a paper published in Physical Review C, the ALICE collaboration reports measurements that quantify the transmutation of lead into gold in CERN’s Large Hadron Collider (LHC).

Transforming the base metal lead into the precious metal gold was a dream of medieval alchemists. This long-standing quest, known as chrysopoeia, may have been motivated by the observation that dull gray, relatively abundant lead is of a similar density to gold, which has long been coveted for its beautiful color and rarity. It was only much later that it became clear that lead and gold are distinct chemical elements and that chemical methods are powerless to transmute one into the other.

With the dawn of nuclear physics in the 20th century, it was discovered that heavy element...

Chirality—the property of an object that is distinct from its mirror image—has long captivated scie...

Using time-lapse videos as training data, computer scientists have developed video generators that simulate the physical world more accurately. While text-to-video artificial intelligence models like OpenAI’s Sora are rapidly metamorphosing in front of our eyes, they have struggled to produce metamorphic videos. Simulating a tree sprouting or a flower blooming is harder for AI systems than generating other types of videos because it requires the knowledge of the physical world and can vary widely.

But now, these models have ta...

In 1959, physicists James Terrell and Roger Penrose (Nobel laureate in 2020) independently concluded that fast-moving objects should appear rotated. However, this effect has never been demonstrated. Now, scientists have succeeded for the first time in reproducing the effect using laser pulses and precision cameras — at an effective speed of light of 2 meters per second.

When an object moves extremely fast — close to the speed of light — certain basic assumptions that we take for granted no longer apply. This is the central consequence of Albert Einstein’s special theory of relativity. The object then has a different length than when it is at rest, and time passes differently for the object than it does in the laboratory. All this has been repeatedly confirmed in experiments.

How...